A protein subunit of human RNase P, Rpp14, and its interacting partner, 01P2, have 3 '-> 5 ' exoribonuclease activity

作者：Jiang TJ; Altman S^*

来源：Proceedings of the National Academy of Sciences of the United States of America, 2002, 99(8): 5295-5300.

DOI：10.1073/pnas.072083699

• tRNA processing
• phosphorolytic enzymes
• exosome

The processing of precursor tRNAs at their 5' and 3' termini is a fundamental event in the biosynthesis of tRNA. RNase P is generally responsible for endonucleolytic removal of a leader sequence of precursor tRNA to generate the mature 51 terminus. However, much less is known about the RNase P counterparts or other proteins that are active at the tRNA 3' terminus. Here we show that one of the human RNase P subunits, Rpp14, together with one of its interacting protein partners, OIP2, is a 3'--> 5' exoribonuclease with a phosphorolytic activity that processes the 3' terminus of precursor tRNA. Immunoprecipitates of a crude human RNase P complex can process both ends of precursor tRNA by hydrolysis, but purified RNase P has no exonuclease activity. Rpp14 and OIP2 may be part of an exosome activity.

• 出版日期2002-4-16